1. Field of the Invention
The present invention relates in general to an elongated flexible tape having flat, spaced conductors for detecting liquid leaks, and a method for using the same.
2. Description of the Prior Art
Water and other liquid leaks have long been a problem to homeowners. For example, many homes have air conditioning units with air handlers that are located in the home's attic. These units include evaporators that generate large quantities of condensation that must be collected, and removed through a small drain pipe. It is quite common for the drain pipes to become clogged, and cause the condensation to back up and overflow onto the floor of the attic. Since the residents of the home typically do not check the condition of the unit, the overflowing condensate is usually not detected until it does substantial, costly damage to the ceilings of the rooms below. Hot water heaters are another example of devices that are prone to leak, but which leaks typically go unnoticed until substantial water damage has been done. Likewise, leaky basements and roofs are also apt to go unnoticed until substantial damage has been done to the floor, roof, furnishings and other items in the house.
To address this problem, numerous leak detection systems and methods have been proposed. For example, many electrically operated leak detection devices are available that sense the presence of water or liquid by detecting a change in electrical resistance or impedance between two or more conductors that are exposed to the liquid. While these devices generally work well, they suffer from a number of limitations that inhibit their use in certain applications. For example, in circumstances where it is desirous to monitor a large area, such as a roof or a perimeter of a basement, present systems require the use of time domain reflectometry (TDR), or some other technique, to detect the location along the pair of conductors in the monitored area where a leak occurs. This is because a simple short circuit detection circuit is not capable of detecting the location along a pair of conductors where a short circuit created by water or other conductive liquid bridging the conductors occurs. TDR works by sending a signal along the conductors and detecting the reflection of the signal that is generated at the point where an impedance change occurs between the conductors. Through phase analysis of the reflected signal, the distance along the conductor where a conductive liquid that is present can be determined. While TDR based systems work well, they are much more costly than simple short circuit detectors.
Another problem with previous electrically operated leak detection systems is that they are typically only effective in sensing fairly large quantities of water or other liquid. This is because they employ spaced apart conductors that are too thick, and essentially act as a dam to small quantities of water that prevent the water from traveling past a first conductor into contact with a second conductor, and thereby triggering the leak detector. While this problem may not be a concern in applications where only large quantities of leaking liquid need to be detected, it is a notable concern in numerous other applications, including those discussed previously where water leaking from evaporation units, hot water heaters, toilets and other fixtures, basements and roofs, is to be detected. In these applications, it is imperative that any water leakage be detected as soon as possible to minimize the likelihood that serious water damage will occur. It is therefore desirous that even a few drops of water be detected by the leak detection system so that an individual will be given the earliest warring possible that a leakage problem has developed.